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1.
Risperidone is a new benzisoxazole derivative displaying a very potent serotonin antagonism and a potent dopamine antagonism in pharmacological studies. These properties suggest the hypothesis that risperidone may exert antipsychotic effects and be superior to classic neuroleptics in its beneficial effects on negative and affective symptoms and its low extrapyramidal side-effect propensity. In an open pilot study 13 patients suffering from acute schizophrenic psychosis were treated with risperidone within an individually adapted dose range from 1 to 10 mg per day. A good antipsychotic efficacy could be demonstrated in 6 of the 8 patients who completed the trial. Risperidone was very well tolerated. The substance possesses a low EPS-inducing profile. Future research has to test the suggested advantage of risperidone over other neuroleptic drugs and its performance in the treatment of chronic schizophrenic patients. 相似文献
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In the pentastomidRaillietiella aegypti the structure of the genital apparatus and of oogonia, previtellogenic and vitellogenic oocytes was studied by light and electron microscopy. The ovarian wall consists of a single-layered epithelium covered by a basement membrane of varying thickness. The ovary is characterized by numerous, lateral, sac-like evaginations in which the oocytes lie.Centrioles indicate mitotic activities in oogonia. In previtellogenic oocytes the ooplasm is poor in organelles, containing only a few mitochondria and rough endoplasmic reticulum, but many free ribosomes. In vitellogenic oocytes there is a rapid multiplication of mitochondria and a proliferation of the rough endoplasmic reticulum. The cytoplasm also contains cortical vacuoles, yolk spheres, dictyosomes and pinocytotic vesicles. The mitochondria lie in one big cluster and combine to the Balbiani body (=yolk nucleus). Two types of yolk spheres differing in morphological details are formed in the oocytes ofR. aegypti. 相似文献
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Dopamine D3 agonists into the substantia nigra aggravate cataplexy but do not modify sleep 总被引:1,自引:0,他引:1
We have recently demonstrated that local perfusion of dopaminergic D2/D3 agonists into the ventral tegmental area (VTA) significantly aggravates cataplexy and increases sleep in narcoleptic Dobermans. We further assessed the roles of the mesostriatal dopaminergic system and found that local perfusion of quinpirole and 7-OH-DPAT into the substantia nigra (SN) significantly aggravated cataplexy, while perfusion of a D2/D3 antagonist significantly reduced cataplexy. Neither a D1 agonist nor a D1 antagonist modified cataplexy. SN perfusion of quinpirole did not significantly modify sleep, while VTA perfusion significantly increased the drowsy state. Although autoregulation of the VTA and SN dopaminergic neurons are involved in the regulation of cataplexy, both structures have distinct roles for the regulation of sleep. 相似文献
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John T. Riehl MD Adam Sassoon MD Keith Connolly BS George J. Haidukewych MD Kenneth J. Koval MD 《Clinical orthopaedics and related research》2013,471(12):3956-3960
Background
Although gunshot injuries are relatively common, there is little consensus about whether retained bullets or bullet fragments should be removed routinely or only in selected circumstances.Questions/purposes
We performed a systematic review of the literature to answer the following questions: (1) Is bullet and/or bullet fragment removal from gunshot injuries to the pelvis or extremities routinely indicated? And, if not, (2) what are the selected indications for removal of bullets and/or bullet fragments?Methods
A search of the English-language literature on the topic of gunshot injury and bullet removal was performed using the National Library of Medicine and MEDLINE® and supplemented by hand searching of bibliographies of included references. Studies were included if they provided clinical data on one or both of our study questions; included studies were evaluated using the levels of evidence rubric. Most studies on the subject were expert opinion (Level V evidence), and these were excluded; one Level III study and seven Level IV studies were included.Results
No studies provided a rationale for routine bullet removal in all cases. The studies identified bullet fragment removal as indicated acutely for those located within a joint, the palm, or the sole. Chronic infection, persistent pain at the bullet site, and lead intoxication were reported as late indications for bullet removal.Conclusions
The evidence base for making clinical recommendations on the topic of bullet and bullet fragment removal after gunshot injury is weak. Level I and II evidence is needed to determine the indications for bullet removal after gunshot injury. 相似文献8.
Identification of a protein associated with p21ras by chemical crosslinking. 总被引:4,自引:3,他引:4
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J de Gunzburg R Riehl R A Weinberg 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(11):4007-4011
The products of the ras oncogenes (p21ras) are ubiquitous membrane-associated proteins that bind guanine nucleotides and possess an intrinsic GTPase activity. Because of their functional homologies with regulatory guanine nucleotide-binding proteins, they are thought to be involved in the control of cellular proliferation as transducers of incoming growth signals. In an effort to identify proteins interacting with p21ras, we have used in vivo crosslinking techniques on Rat-1 fibroblasts and derived cell lines overexpressing p21ras and immunoprecipitation with polyclonal anti-p21ras antibodies. Under those conditions, using the homobifunctional crosslinker dithiobis(succinimidyl propionate), a protein of Mr 60,000 (p60) is found to be associated with p21ras, and this association is enhanced by the treatment of quiescent cells with serum. Upon sedimentation of detergent extracts from crosslinked cells on sucrose gradients, a p21-p60 complex could be demonstrated with a Mr of 200,000-300,000, p60 does not appear to be related to pp60src nor to the cytosolic GTPase activating protein that interacts with p21ras to enhance its GTPase activity. The amount of p60 seems to be limiting relative to p21ras in fibroblasts, since similar levels of p60 are immunoprecipitated from Rat-1 cells and transfectants overexpressing Ha-, Ki-, and N-ras p21s; the same protein is also found to associate with p21ras in numerous mammalian cell lines. The relevance of this component to the role of ras proteins in signal transduction is discussed. 相似文献
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v. Zeissl Horovitz Hochsinger Caspary Riehl Finger 《Archives of dermatological research》1886,13(1):298-315
Ohne Zusammenfassung 相似文献
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